Using SAR offset-tracking approach to estimate surface motion of the South Inylchek Glacier in Tianshan

Jia Li, Zhi Wei Li, Chang Cheng Wang, Jian Jun Zhu, Xiaoli Ding

Research output: Journal article publicationJournal articleAcademic researchpeer-review

13 Citations (Scopus)

Abstract

Glaciers are characterized by their flowability. Measurement of their velocity can provide important information for the study of glacier mass balance and glacier involved hazards. This paper applies seven ALOS/PALSAR images and the offset-tracking method to derive the displacement field of the largest mountain glacier in Asia, i.e., the South Inylchek Glacier. The temporal continuity of SAR images and the debris coverage of South Inylchek Glacier make the offset-tracking method successfully acquire continuous surface displacements. Several natural events such as snowfall in the firn basins, ablation of superimposed ice and development of crevasses in steep sections still have some influence on the results. However, the derived surface displacement maps of different periods are highly consistent with each other. The detail analysis reveals the following rules of the South Inylchek Glacier's motion: the velocity reduces from glacier axis to both sides, and increases from its origin to snowline and then reduces towards the end; the velocity is positively and nonlinearly correlated with the slope, especially when the slope increases sharply from 1° to 16°, the surge velocity will give rise to crevasses on the glacier; under the influence of glacial lake level changes, the velocity of tributary at the tail can surge to 96 cm/d; the summer velocity is 5~10 cm/d higher than winter one. Seen from all results, the normal velocity of the glacier trunk is between 20 and 50 cm/d, but can reach 65 cm/d in special place. The statistics of sampling points in the tongue indicates that mean velocity of different periods lies between 27.9 and 33.3 cm/d. Compared to the record in 2004, velocity derived in this research reduces about 5 cm/d.
Original languageChinese (Simplified)
Pages (from-to)1226-1236
Number of pages11
JournalActa Geophysica Sinica
Volume56
Issue number4
DOIs
Publication statusPublished - 1 Jan 2013

Keywords

  • Flow velocity
  • Glacier
  • Mass balance
  • Offset-tracking
  • South Inylchek

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology

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